-33.47% is the change from 962 to 640
Calculation steps:
[( 640 - 962 ) ÷ 962] x 100 = -33.47%
Formula
Percentage change = [(640 - 962) / 962] x 100
Subtract the new number by the original number
640 - 962 = -322
-322 ÷ 962 = -0.33471933471933474
-0.33471933471933474 x 100 = -33.47%